There's a good reason for this. It's because the human can be interrogated into what was going through their mind whereas many ML models cannot. That means we can't ascertain if the ML accident is part of a latent issue that may rear its ugly head again (or in a slightly different manner) or just a one-off. That is the original point: a theory-of-mind is important to risk management. That means we will struggle to mitigate the risk if we don't "hyperanalyze" it.
(Linking to the web.archive version because the graphics are better / more understandable when in the context of some of the text)
Chapter 6 is the most relevant here, but it's all a thought provoking story.
Cars can do unexpected things for good reasons, as the AI did in this case.